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VHF/UHF TRANSCEIVER S-14914XZ-C1 March 2013...
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8. READ the instructions of the test equipment thoroughly before connecting it to the transceiver. Icom, Icom Inc. and the Icom logo are registered trademarks of Icom Incorporated (Japan) in Japan, the United States, the United Kingdom, Germany, France, Spain, Russia and/or other countries.
Internal speaker • Power supply : 10.0–16.0 V DC for external DC : More than 0.2 W with a 8 Ω load External speaker power, or specifi ed Icom’s battery • Selectivity pack : More than 55 dB (Wide) • Digital transmission speed : 4.8 kbps...
SECTION 2. INSIDE VIEWS • LOGIC UNIT EEPROM (IC3) LEVEL CONVERTER (IC21) DSP FLASH MEMORY (IC20) MIC MUTE SW (IC16) EEPROM (IC7) MODE SW (IC390) AF FILTER (IC350) (IC5) AF AMP (IC2) AF AMP (IC300) CLOCK OSCILLATOR (For the CPU) TONE FILTER (X2) (Q330)
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• MAIN UNIT (TOP VIEW) POWER AMP (Q45) APC AMP (IC14) CURRENT DETECTOR 3VS LINE REGULATOR (IC5) (IC12) VCC LINE SW (Q907) (Q8) (Q906) VCC LINE SW RF AMP (Q2) (Q780) D/A CONVERTER (IC952) LOCK VOLTAGE BUFFER (Q451) PLL IC (Band B) (IC450) +5 V REGULATOR (IC15)
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• MAIN UNIT (BOTTOM VIEW) DRIVE AMP (Q41) VHF RF AMP (Band A/B) (Q702) UHF RF AMP (Band A/B) (Q602) VHF RF AMP (Band A) (Q701) UHF RF AMP (Band A) (Q601) UHF RF AMP (Band B) (Q641) 1ST IF FILTER (Band A) (FI3) VHF RF AMP (Band B) (Q740)
1) Remove 2 dials and antenna nut from the front panel. 5) Unsolder 6 points at the rotary encoder. Inner dial UNSOLDER Screws x5 Antenna nut Outer dial Remove with; “ICOM Driver (Q)” Solder (8960000370) remover LOGIC UNIT 2) Remove 2 screws from the bottom of chassis. Screws Rotary encoder 6) Separate the LOGIC UNIT from the chassis, and then disconnect the fl...
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2. REMOVING THE MAIN UNIT 3) Unsolder a point at the antenna connector. 1) Unsolder 2 points on the shield plate. UNSOLDER UNSOLDER Solder remover Solder remover Shield plate 4) Remove 6 screws from the MAIN UNIT, and then 2) Remove 5 screws from the shield plate, and then remove the MAIN UNIT from the chassis.
SECTION 4. CIRCUIT DESCRIPTION UHF BAND (380–479 MHz) 4-1 RECEIVE CIRCUITS The RF signal from the antenna is passed through the HPF RF CIRCUITS (L512, L514, C545, C548, C550, C551 and C554), two LPFs VHF BAND (108–174 MHz) (L511, C536, C539 and L507, C524, C526, C529), ANT SW The RF signal from the antenna is passed through two LPFs (D508 and D510) and BPF (L608, L610, L612, C630, C631 (L513, L515, L516, C547, C549, C553, C555 and C556),...
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1ST IF CIRCUITS UHF BAND (380–479 MHz) VHF BAND (108–174 MHz) • Band A • Band A (137–174 MHz) The RX signal from the RF circuit is applied to the 1st mixer The RX signal from the RF circuit is applied to the 1st mixer (Q801) and mixed with the 1st LO signal, resulting in the 46.35 (Q820) and mixed with the 1st LO signal, resulting in the 46.35 MHz 1st IF signal.
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2ND IF CIRCUITS • Band B • Band A The 1st IF signal from the 1st IF circuit is applied to the IF IC The 1st IF signal from the 1st IF circuit is applied to the IF IC (IC901, pin 16), which contains the 2nd IF AMP, 2nd mixer, (IC13, pin 16), which contains the 2nd IF AMP, 2nd mixer, FM FM demodulator, and so on.
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DIGITAL DEMODULATION CIRCUIT (LOGIC UNIT) RADIO RECEIVE CIRCUITS While operating in the DV mode, the demodulated signal • FM BAND (76–108 MHz) (digital audio signal) is passed through the LPF (R305, R336, The RF signal from the antenna or earphone is passed through R339, C334 and C337) and amplifi...
MODULATION CIRCUITS (MAIN UNIT) 4-2 TRANSMIT CIRCUITS The MIC signal from the TX AF circuits is applied to the VHF TX AF CIRCUIT (LOGIC UNIT) VCO (Q311, D304–D306) or UHF VCO (Q27, D10–D12) as The AF signal from the internal or external microphone (MIC a modulation signal.
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TX AMP CIRCUITS (MAIN UNIT) APC CIRCUITS (MAIN UNIT) The TX signal is passed through the buffer (Q48) and ATT The voltage produced at the LPFs (VHF band; L513, L515, (D20, D21), which controls the TX output power by the APC L516, C547, C549, C553,C555 and C556, UHF band;...
UHF VCO (VCO1 UNIT) 4-3 FREQUENCY SYNTHESIZER CIRCUIT The UHF VCO (Q27, D10–D12) generates 1st LO signal (MAIN UNIT) (for receiving a UHF signal on band B). The output of buffer VCOs (Q200) is amplifi ed by the LO AMP (Q201), and then used as The ID-51A/E has total of four VCOs;...
4-4 PORT ALLOCATIONS • CPU (LOGIC UNIT: IC5) Line Name Description Line Name Description VOX sensing voltage. DICK1 [DIAL] (outer dial) (S12) phase-A TSQL/DTCS tone signal. (Band PLL unlock detection. (Band A) ACTCIN AUNLK L=Unlocked. CLSFT2** Clock frequency shift control. DALD D/A converter serial strobe.
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• CPU (LOGIC UNIT: IC5) (continued) Line Name Description Line Name Description IOEN Expander chip enable. EEPROM serial clock. DSP clock shift control. microSD card insert detection. DCSFT SD_SENC L=+600 Hz shifted. L=Inserted. BPLLSTB PLL serial strobe. (Band B) Serial data to the attached mi- SD_TXD croSD card.
SECTION 5. ADJUSTMENT PROCEDURE 5-1 PREPARATION ¤ REQUIRED EQUIPMENTS EQUIPMENT GRADE AND RANGE EQUIPMENT GRADE AND RANGE Voltage range : 1–15 V Modifi ed 3-conductor plugs Power supply JIG cables Current capacity : More than 3 A (See the illustration below) Audio generator Frequency range : 300–3000 Hz...
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• ENTERING THE ADJUSTMENT MODE 1) Connect the JIG cable “#1” to [SP]. (See page 5-1) 2) While holding down [SQL] and , turn ON the power. [SQL] Connect the JIG cable “#1” (See page 5-1) here. Push to turn ON the power. [QUICK/MENU] •...
5-2 FREQUENCY ADJUSTMENT Select an adjustment item using , and then set the adjustment value as specifi ed using [DIAL]. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM REFERENCE 1) Set the power supply voltage to 7.4 V. FREQUENCY 2) Connect a power meter or dummy load to the antenna connec- Displayed tor.
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5-3 TRANSMIT ADJUSTMENT (Continued) • IDLING CURRENT ADJUSTMENT (at 7.4 V) Select an adjustment item using , and then set the adjustment value as specifi ed using [DIAL]. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM DRIVE AMP 1 1) Set the power supply voltage to 7.4 V. IDLING CURRENT 2) Connect an RF power meter to the antenna connector.
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5-3 TRANSMIT ADJUSTMENT (Continued) • IDLING CURRENT ADJUSTMENT (at 13.5 V) Select an adjustment item using , and then set the adjustment value as specifi ed using [DIAL]. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM DRIVE AMP 1 1) Set the power supply voltage to 13.5 V. (supplying from [DC IN]) IDLING CURRENT 2) Connect an RF power meter to the antenna connector.
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5-3 TRANSMIT ADJUSTMENT (Continued) • TRANSMIT POWER ADJUSTMENT (at 5.5 V) Select an adjustment item using , and then set the adjustment value as specifi ed using [DIAL]. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM TRANSMIT 1 1) Set the power supply voltage to 5.5 V. POWER 2) Connect an RF power meter to the antenna connector.
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5-3 TRANSMIT ADJUSTMENT (Continued) • TRANSMIT POWER ADJUSTMENT (at 13.5 V) Select an adjustment item using , and then set the adjustment value as specifi ed using [DIAL]. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM TRANSMIT POWER 1 1) Set the power supply voltage to 13.5 V. (supplying from [DC IN]) –...
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5-3 TRANSMIT ADJUSTMENT (Continued) • DEVIATION ADJUSTMENTS Select an adjustment item using , and then set the adjustment value as specifi ed using [DIAL]. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM FM DEVIATION 1 1) Set the power supply voltage to 7.4 V. 2) Connect a modulation analyzer to the antenna connector through an attenuator, and set it as;...
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5-3 TRANSMIT ADJUSTMENT (Continued) • DEVIATION ADJUSTMENTS (Continued) Select an adjustment item using , and then set the adjustment value as specifi ed using [DIAL]. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM DV BALANCE 1 1) Set the power supply voltage to 7.4 V. 2) Connect a modulation analyzer to the antenna connector through an attenuator, and then set it as;...
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5-3 TRANSMIT ADJUSTMENT (Continued) • TONE DEVIATION ADJUSTMENTS Select an adjustment item using , and then set the adjustment value as specifi ed using [DIAL]. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM TONE DEVIATION 1 1) Set the power supply voltage to 7.4 V. 2) Connect a modulation analyzer to the antenna connector through an attenuator, and then set it as;...
5-3 TRANSMIT ADJUSTMENT (Continued) 5-4 RECEIVE ADJUSTMENTS 1) Select an adjustment item (band) using 2) Set the SSG as specifi ed (frequency, deviation and output level), and then push to automatically adjust. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM RECEIVE NOTE: “RECEIVE SENSITIVITY” must be adjusted before “S-METER.” Otherwise, “S-METER” will SENSITIVITY not be adjusted properly.
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5-3 TRANSMIT ADJUSTMENT (Continued) 5-4 RECEIVE ADJUSTMENTS (Continued) 1) Select an adjustment item (band) using 2) Set the SSG as specifi ed (frequency, deviation and output level), and then push to automatically adjust. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM S-METER NOTE: “RECEIVE SENSITIVITY” must be adjusted before “S-METER” and “S-METER S3 LEVEL.” Other- [A-BAND] wise, “S-METER”...
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5-3 TRANSMIT ADJUSTMENT (Continued) 5-4 RECEIVE ADJUSTMENTS (Continued) 1) Select an adjustment item (band) using 2) Set the SSG as specifi ed (frequency, deviation and output level), and then push to automatically adjust. ADJUSTMENT ADJUSTMENT OPERATION VALUE ITEM SQUELCH 1 1) Set the power supply voltage to 7.4 V. –...
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The combination of top side and bottom side of this SECTION 9. BOARD LAYOUTS • LOGIC UNIT (TOP VIEW) DS12 C394 R391 Q390 R395 R396 LCDCS LCDRES LCDRS LCDCK LCDDT DS11 DS10 R398 R397 C399 C517 C398...
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The combination of top side and bottom side of this • LOGIC UNIT (BOTTOM VIEW) [PWR] R419 R119 R237 C103 R112 R198 R118 R239 R242 R113 C107 C171 R227 R109 C311 R108 C132 IC20 R217 C102 R222 [DIAL] R314 C305 R308 R181 R418...
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The combination of top side and bottom side of this • MAIN UNIT [MIC] [SP] [DC IN] (TOP VIEW) IC15 R169 C177 C136 C194 R171 IC12 C198 R112 C989 EP13 EP15 R110 C210 C102 C230 C110 R113 C237 C991 C468 R203 R183 R466...
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The combination of top side and bottom side of this • MAIN UNIT (BOTTOM VIEW) C221 EP12 EP784 R192 C224 R201 EP11 C220 C796 C797 EP10 EP785 EP782 R273 MP12 C446 MP13 C448 C445 R200 R170 R209 EP23 C977 C235 D820 C200 R820...
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SECTION 10. BLOCK DIAGRAM EARANT BTL4.2V BTL4.2V FMPTX RADIO BUFF IC20 AFON CLONE IC25 IC25 D_AS MAIN UNIT DTCS EXTMIC IC25 VCOMOD CHASSIS UNIT MMUTE LINEAR MODE REFMOD CTCOUT CODEC DMOD IC25 IC16 IC390,Q390 AUSTB MMUTE PLAY SC_CLK SC_SDI SC_SDO IC25 SC_LR DAFO...
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